Motorman&#39;s valve.



N0.`80l,363. PATENTED OCT. 10, 1905.v F. B. COREY. MOTORMANS VALVE.

APPLICATION FILED APR 27. 1903.

Inventor Fred Corey. by @aww/@dmv hhnunm v. A Y K 7 LAF' Witnesses i 6^UNITED STATES PATENT OFFICE.

FRED B. COREY, OF SCHENECTADY, NElN YORK, ASSIGNOR TO GENERAL ELECTRICCOMPANY, A CORPORATION OF NEW YORK.

IVIOTORNIANS VALVE.

Speccation of Letters Patent.

Patented. Oct. 10, 1905.

l Application filed April 27, 1903. Serial No. 154,430.

A il) @ZZ whom it nba/y concern:

Be it known that I, FRED B. CoREY, a citizen of the UnitedStatesresiding at Schenectady, county of Schenectady, State of New York,have invented certain new and useful Improvements in Motormens Valves,ofwhich n the following is a speciiication.

My invention relates to improvements in valves em lo ed by engineers andmotormen .Y z= tor controlling the application and release of brakes inso-called straight-air systemsthat is, systems in which the brakes areapplied by increasing the pressure of the air in y brought to bear uponthe brake-shoes without causing the wheels to skid than when the trainis moving` at a low speed. Therefore if air is admitted into thetrain-pipe at a high pressure while the train is running at full speedand the pressure is gradually reduced as the speed decreases, so thatthe wheels of the train may be maintained throughout the entire time ofmaking a stop just on' the point of skidding, a maximum braking eiiectwill be obtained.

One object of my invention is to produce a valve for use in straight-airsystems by which this maximum braking effect is produced, and this,generally stated, is accomplished by providing in the ordinary engineersstraight-air valve means so related to the train-pipe connections and soadjusted that it will open said train-pipe through a contracted passageto atmosphere when the pressure in such trainpipe rises above apredetermined'point, thereby allowing said train-pipe pressure, andconsequently the brake-shoe pressure, to decrease as the speed of thetrain decreases.

In air-brake systems it is a common practice to provide some means otherthan the engineers or motormans valve by which the brakes may be appliedin case of emergency; but such means are ineffective when the motormansvalve is left in quick-release position, which is the position instraight-air systems in which train-pipe is connected directly toatmosphere through a wide opening.

Another object of my invention is to provide a novel means for avoidingthis contingency by which when the valve is moved by the hand to thequick-release position and the hand is removed the valve willautomatically move from said position to another which will not renderthe operation of the emergency means ineective.

Other objects and advantages will appear from the following detaileddescription, taken in connection with the accompanying drawings, inwhich- Figure 1 is a sectional View of a valve embodying the variousfeatures of my invention. Fig. 2 is a partial sectional View of thevalvehandle. Fig. 3 is a partial section of the valve-body and therelief-valve, taken on a plane at right angles to that of Fig. 1. Fig. 4is a top view of the relief-valve, drawn to an enlarged scale. Fig. 5 isa section of a portion of the valve-bonnet and the head fittingthereover, taken on theline 5 of Fig. 1. Fig. 6 is a top view of thevalve-body and represents diagrammatically the position of thevalve-ports for the lap position` and the various operative positions ofthe handle. Fig. 7 is a top view of the complete valve, and Fig. 8 is asimilar view of the main valve.

In the drawings, in which like characters refer to like parts, 1designates the valvebody, which is provided with suitable apertured lugs2, by which i-t may be secured to any suitable support.

3 designates the valve-bonnet,- which is secured to the body 1 by bolts4 4, and 5 designates a gasket interposed between `the bonnet 3 and thebody 1.

The main reservoir, train-pipe, and atmosphere connections R2 T2 A2communicate through corresponding passages R T A with the ports R-T A inthe Valve-body 1. The upper surface of the valve-body 1 forms a seat forthe rotary valve 6, which is adapted through suitably connected ports 7and 8 (shown in dotted lines, Figs. 6 and 8) to connect the train-pipeeither to main reservoir or atmosphere. The lower part of this ro taryvalve 6 is provided with a central proiection 9, engaging in a centralsocket 10 in the valve-seat, and a suitablev oil-passage 1l IOS enablesthe parts to be properly lubricated. The upper surface of this rotaryvalve 6 is provided with lugs 12 13, between which the lug 14 on thelower end of the valve-stem 15 is adapted to rest when the parts are inposition. A spring 16, extending into sockets 17 and 18 in the rotaryvalve 6, and the stem 15, respectively, insures a satisfactoryengagement of the valve 6 with its seat. The valvestem 15 is providedwith an oil-hole 19, having a suitable screw-cap 20, through which oilmay pass to the socket 17 and the oil-hole 11, and the upper end of thestem 15 is suitably shaped for the reception of the handle H.

Screwed into the lower side of the valvebody 1 is a casing 22, theinterior of which communicates with the passage r in the valvebody. lnthe upper end of this casing is a valve-seat 23, against which a valve24 is normally pressed by a spring 25; An adjusting'- screw 26, providedwith a uut 27, enables the tension of the spring 25 to be adjusted. Theinterior of the casing 2Q is in constant cornmunication with theatmospheric passage A through an opening' 28 in said casing and anopening 29 in the valve-body 1. Lhe upper end of the valve 24 islongitudinally grooved, as clearly indicated in Fig. 4, so that when thevalve is forced downward against the pressure of the spring 25communication may be readily had between the passages rlV and A throughthe openings 28 and 29.

Mounted upon the upper end of the valvebonnet 3 is a head 30, which litsabout a portion of the upper end of said bonnet and through the agencyof a spring 31, one end of which is iixed to the head and the other ofwhich is fixed to the bonnet, is normally held in the positionillustrated by full lines in Fig. 5, in which position a stop 32 on thehead engages a stop 33 on the bonnet 3. When the handle H is in positionon the valve-stern 15, a projection 34 just below the pawl 35 on thehandle lies in the same horizontal plane as the projections 86 and 37 onthe head 30 and is adapted, therefore, to engage said projections whenmoved to certain operative positions. ln Fig. 5 the dotted-line positionof the parts illustrates how the projection 34 on the handle by engagingthe projection 37 on the head will rotate said head againstthe tensionof the spring 31 until the stop 38 engages With the stop 33. As thesestops are arranged the projection 34 on the handle H does not engage thestop 37 on the head 30 until the handle in moving toward the left hasmoved the valve 6 to the A"slow-release and running position, so thatthe head 30 is not moved by the movement of the handle between any ofthe operative positions to the right of the slow-release and runningposition; but when it is attempted to move the handle to the left ofthis position the resistance of the spring 31 is encountered, and shouldthe hand of the motorman be removed from the handle while it is at anypoint between the slow-release and running and the y quick-releasepositions or at the quick-release position it would immediately bereturned by the action of the spring 31 and head 30 to the slow-releaseand running position.

The handlel H is provided with a head 39, apertured so as to closely titthe upper end of the valve-stem 15 and having a cap 40 to close saidopening and cover said stern when the handle is in position. Screwedinto the head 89 is a stem 41, in which is located a spring 42, employedto hold the pawl 35 in its outward position against the stop 43. Acap-nut 44 is applied to the other end of the stem 41, and therebysecures in place a sleeve 45. The

pawl 35 is adapted to engage a notched flange 47 at the upper end of thehead 30 and to determine the various operative positions of the mainvalve by engagement with the shoulders on said flange. r1`he projection34 on the handle H passing under the flange 47 retains the handle inplace on the valve-stein 15 and prevents its removal, except when theprojection is brought opposite the notch 48 in said fiange and the mainvalve is in the lap position, which is that illustrated in Figs. 6 and7. In the lap position none of the ports in the valve 6 communicate withthe ports in the valve-seat, so that for this position the mainreservoir and train-pipe are completely cut olf.

ln the operation of the valve after the handle H has been put in placeon the valve-stem 15, which is done while the valve 6 is in the lapposition, if it is desired to start the car or train the handle H ismoved to the slowrelease and running position, thereby connect ingtrain-pipe to atmosphere through a contracted passage formed by theextension 46 of the valve-port 7 and a small portion of the valve-port8, overlapping the seat-ports T and A, respectively, and thereby slowlyexhausting the train-pipe if it still contains any air above atmosphericpressure, so as to fully release the brakes. The handle is then retainedin this position while the car or train is running and until it isdesired to make a stop. In making the usual or service stop the handle His moved from the slow-release and running position to the servicestopposition and held there only a short time, after which it is returned tothe lap position. The movement to the service-stop position causes thevalve-ports 7 and 8 to overlap portions of the seat-ports R and T. thusconnecting the main reservoir to train-pipe through a contracted passageand applying the brake. The extent of the braking action depends uponthe length of time this connection is maintained, and this in turndepends upon the judgmentof the motorman in making the application. 1f asingle movement to service-stop position and return to lap produces aninsufficient application ofthe brakes, the movement may be repeated asmany times as nec- IOO IIO

ISO

essary. Each time the handle H is moved to theservice-stop position airat reservoir-pressure, which here will be assumed to be one hundredpounds to the square inch, rushes into the train-pipe and increases theair-pressure in said pipe to a point depending' upon the length of timethe handle is held in the service-stop position. It this time issufficiently long, the train-pipe pressure will increase to that or'main reservoir-viz., one hundred pounds-and if of less duration therewill be a correspondingly smaller resulting pressure. If this resultingpressure be above that for which the relief-valve 24 is setwsay sixtypounds per square inch-said valve will be opened and the train-pipepressure gradually reduced, through the agency of the exhaust-openings28, Q9, and A', toa point which will permit the valve 24 to close. Themaximum and minimum pressure limits here assumed as one hundred poundsand sixty pounds, respectively, may of course be varied to suit theconditions or' any given case. The maximum train-pipe pressure willordinarily be such that it will produce a maximum braking' ei'ectwithout skidding the wheels when the speed or' the train or car is amaximum, and the minimum pressure will be such as to produce a maximumbraking effect without causing the wheels to skid when the speed becomesZero. Under these conditions, assuming that the car or train is movingat a maximum speed and it is desired to make a quick service stop, thehandle H will be thrown over from the slow release and running positionto the service-stop position and held there until the train-pipepressure has increased to a maximum and then to be returned to lapposition. As soon as the train-pipe pressure reaches a maximum a maximumbrake-shoe pressure is applied, and this with the low coercient offriction which exists at maximum speed causes aderinite braking effectwhich, due to the proportion of the various parts, is the great-est thatmay be applied without causing the wheels to skid. As the speed of thetrain decreases, and consequently the coecient of friction increases,the train-pipe pressure, and consequently the brake-shoe pressure,through the action of the relief-valve, correspondingly decrease, so thatthe braking effect is still the highest permissible-viz., such as tokeep the wheels on the point or' skidding-and this maximum brakingeffect is obtained at every instant of the time consumed in making thestop. It' for any reason the train or car must be stopped suddenly, thehandle H is moved to the extreme right to the position designatedEmergency-stop, at which position the valve-ports 7 and 8 registerexactly with the ports R and T, respectively, thus connecting train-pipewith main reservoir through a large opening and enabling the train-pipepressure to be increased suddenly to that of main reservoir, therebyproducing an immediate maximum application of the brakes. When it isdesired to release the brakes, the handle H may be removed to eitherslow release and running or to quick-release posi-- tion. When moved tothe former position, as above indicated, the extension 46 of the port Toverlaps the port T and connection through a contracted passage is madefrom train-pipe to atmosphere. This allows the train-pipe pressure togradually fall to that of atmosphere, and thereby gradually release thebrakes. When the handle is moved to the quick-release position, theports 7 and 8 register with the ports T and A, respectively, thusconnecting train pipe to atmosphere through a large opening' andallowing the train-pipe pressure to be decreased suddenly to that ofatmosphere.

The purpose of the contracted passage between train-pipe and atmosphereof the slow release and running position in addition to the wide passageof the quick-release position is to enable this valve to be used with anemergency device such as is commonly employed for applying the brakes.Since it is necessary to keep the train-pipe pressure at that ofatmosphere while running, and since the brakes in a straight-air systemcan only be applied by admitting air under pressure to the train-pipe,it is clear that the emergency device would be inett'ective if themotormans valve were maintained in the quick-,release position, becauseof the wide opening between train-pipe and atmosphere in this position.On the other hand, the contracted passage of theslow release and runningposition will maintain' the train-pipe at atmospheric pressure whilerunning and also permit a sufficient increase of train-pipe pressure toapply the brakes when the emergency device is operated.

The purpose of the yieldingly-mounted head 30 and its cooperating stopspreviously described is to return the Valve 6 from quickrelease positionto slow release and running position in case of injury to the motormanor carelessness yon his part in leaving said valve in the quick-releaseposition, so that unless wilfully held in the quick-release position thevalve will not prevent an effectual operation of the emergency device toapply the brakes.

Although I have shown and described the features of my invention inconnection with a valve for use instraight-air systems, it is clear thatthe mechanism which I have disclosed for returning the valveautomatically to a given position when it has been moved manually beyondthat position is equally applicable to automatic air systems in the samemanner as the construction disclosed in the patent to Howe and Gartner,No. 321,971, July 14, 1885, and, further, I do not Wish to be limited tothe specific construction herein disclosed, but aim to cover in theappended claims all modiications and alterations which IOO IIO

may fall within the spirit and. scope of my invention.

What I claim as new, and desire to secure by Letters Patent of theUnited States, s-

1. In a .straight-air brake system, a main valve constructed andarranged to connect the passage leading to the brake-cylinder to mainreservoir to apply the brakes and to atmosphere to release the brakes,-and a relief-valve connected to said passage and adapted to reducegradually the pressurein said passage to a predetermined point torelieve the pressure on the brakes when the pressure in said passage israised beyond said point by the operation of said main valve.

2. Ina straight-air brake system, amain valve constructed and arrangedto connect the passage leading to the brake-cylinder to main reservoirto apply the brakes and to atmosphere to release the brakes, and arelief-valve connected to said passage and adapted to reduce graduallythe pressure in said passage to a predetermined point to reduce thebrakepressure by an amount sulcient to prevent skidding as the speed ofthe car is reduced.

3. In a controlling-valve for air-brake systems, the combination of amain valve constructed and arranged to connect train-pipe to mainreservoir through wide and restricted passages for different positionsof said valve and to atmosphere through wide and restricted passages forother positions of said valve, and a relief-valve associated with thetrain-pipe passage and adapted to connect said passage to atmospherethrough a small port to gradually reduce the train-pipe pressure to apredetermined point when said pressure is raised beyond said point bythe operation of said Valve.

4. In a controlling-valve Jfor air-brake systems, the combination of amain valve constructed and arranged to connect train-pipe to mainreservoir through wide and restricted passages for different positionsof said valve and to atmosphere through wide and restricted passages forother positions of said valve, a springpressed valve normally closingthe train-pipe passage to atmosphere and adapted to open said passage toatmosphere through a small port when the pressure in said passage risesabove a certain predetermined point.

5. In a controlling-valve for air-brake systems, the combination withthe valve-bonnet, of a rotary valve-stem, a relatively rotatable headsurrounding said stem, a spring connection between the rotatable headand the bonnet of the valve, and means whereby the rotation of thevalve-stem'v beyond a certain point will cause the said head to berotated with the valve-stem.

6. In a controlling-valve for air-brake systems, the combination withthe valve-bonnet, of a rotary valve-stem, an operating-handle therefor,a relatively rotatable head surrounding said stem, a spring connectionbetween said head and the bonnet of the valve, and a projection on thehead adapted to be engaged by the operating-handle when the valve ismoved beyond its running position in adirection to release the brakes.

7. In a straight-air brake system, amainvalve casing comprising avalve-seat therein, passages in said casing below the valve-seat leadingto the brake-cylinder, to the main reservoir, and to the atmosphere,respectively, and a relief-valve inserted in said casing below saidvalve-seat and connected to the brakecylinder passage.

8. In a straight-air brake system, a mainvalve casing comprising avalve-seat therein, passages in said casing below the valve-seat leadingto the brake-cylinder, to the main reservoir, and to the atmosphere,respectively, and a relief-valve inserted in said casing below theValve-seat and connected through said casing with the brake-cylinderpassage, the relief-valve chamber being connected by a small passagethrough said casing with the atmosphere-passage.

In witness whereotl I have hereunto set my hand this 24th day of April,1903.

FRED B. COREY. NVitnesses:

BENJAMIN B. HULL, HELEN ORFORD.

